Display apparatus and method of controlling same

ABSTRACT

A screen display apparatus includes an operation information reception unit that receives operation information regarding an inclination direction and an inclination angle of a joystick from the joystick, and a screen controller that performs a scroll process for scrolling a screen and a zoom process for zooming based on the operation information. The screen controller scrolls the screen according to the inclination direction and the inclination angle of the joystick, and continues a zoom-out process for zooming-out of the screen based on a detection of the inclination angle that is greater than a predetermined angle for a predetermined period until detecting the inclination angle of the joystick to be equal to or smaller than the predetermined angle or until zooming out to a predetermined minimum zoom rate.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.11/715,501 filed on Mar. 8, 2007, which is based on and incorporatesherein by Japanese Patent Applications No. 2006-83695 filed on Mar. 24,2006 and No. 2006-355175 filed on Dec. 28, 2006, the disclosures ofwhich are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention generally relates to a screen display apparatusthat displays information on a screen of a computer or the like, andmore practically, an apparatus that displays a large volume image suchas a map or the like.

BACKGROUND OF THE INVENTION

In recent years, a technique of scrolling is known as a way fordisplaying a large volume of information that can not fit into a screen.The scrolling technique moves a content of the screen in anupward/downward/leftward/rightward direction for displaying a portion ofinformation that spilled over from the screen. However, scrollingthrough a large volume of information requires time and effort due tothe amount of the information to be scrolled. In addition, the contentof information cannot be grasped during scrolling when scrolling speedis increased.

A scale of the image displayed on the screen is changed by zooming inand zooming out. That is, the image “zooms in” when the scale (i.e., ashrinking factor) of the image is decreased, and the image “zoomsout”when the scale of the image is increased. The spilled-over contentcan be included in the screen when the image is zoomed out.

A large portion of conventional screen display apparatuses areconfigured to have different interfaces respectively for scrolling andzooming control. Therefore, the scrolling operation and the zoomingoperation had to be frequently changed for finding a desired portion ofa large volume image. The frequent change of the scrolling operation andthe zooming operation caused hassles to a user of the screen displayapparatus. For example, the image in the screen had to be zoomed out forroughly locating desired information in the zoomed-out image at first,and then the image had to be zoomed in for closely searching the desiredinformation.

A non-patent document 1 discloses a technique that resolves the hasslesof the above operation by combining the scrolling and the zooming. Thisdocument discloses an interface that automatically controls a zoom levelbased on a speed of the scroll operation. This document proposes a basicconcept of a constant scroll speed on the screen regardless of an actualspeed in the information space. In this manner, the scrolling speed thatis too fast to be caught by the eye is prevented. Further, thisnon-patent document proposes a plan that prevents an abrupt zooming outin a high-speed scroll by calculating the zoom level based on a power ofan input value.

[Non-patent document 1] “Effective navigation by an automatic zoomingaccording to a movement speed”by Takeo Igarashi, Ken Hinckley in aproceeding for 8th workshop of interactive systems and software(WISS2000), pp. 57-66, December 2000.

However, the technique in the above-identified non-patent document 1 isthat the speed of the scrolling on the screen (i.e., a visual speed ofscreen) is kept at a constant rate, thereby being unable to scrollthrough the information space over the scroll speed inputted from aninput device. For example, even when the input value of the scroll speeddoubles, the scrolling speed is visually kept constant on the screenwhere the zoom level is changed to ½. In other words, the informationspace is not scrolled through as twice as fast by this technique.Therefore, it takes a long time to find the desired information in thelarge volume of information such as a map or the like.

Further, when a relationship between the input value from the inputdevice and the scroll speed are set so as to access the information farapart in the information space in an appropriate period, the zoom levelbecomes susceptible to a small change in the input value to cause alarge scale change due to the gap of a range of the input value and thescale of the information space as well as the restriction on the inputrange of the input device. Particularly, when the information such as amap or the like is equally beneficial at any level between the zoomed-inimage and the zoomed-out image, a frequent change of the zoom ratecauses problems for practical use.

SUMMARY OF THE INVENTION

In view of the situation described above, the object of the presentinvention is to provide a screen display apparatus having an easilysearchable interface that handles a large volume of information.

The screen display apparatus of the present invention includes anoperation information reception unit that receives operation informationregarding a scroll direction and a scroll speed of a screen from aninput device, and a screen controller that performs a scroll process forscrolling a content of_a screen based on the operation informationreceived by the operation information reception unit and performs a zoomprocess for changing a zoom rate of the screen based on a scroll timeand a scroll speed of scrolling in a same scroll direction.

In this manner, scroll time information derived from the operationinformation that represents the scroll direction and the scroll speed isutilized for changing a zoom rate, thereby enabling an automatic zoomrate change by a scroll operation. In addition, since the zoom rate isnot controlled to be proportional but associated with the scroll speedand a scroll time of the scroll in the same direction, the zoom ratecontrol is prevented from suffering from a frequent change due to thechange of the scroll speed.

A method for displaying a screen of the present invention includes astep for receiving operation information regarding the scroll directionand the scroll speed from the input device, and a step for performingthe zoom process for changing the zoom rate based on the scroll time andthe scroll speed in the same direction with performing the scrollprocess for scrolling a content of a screen based on the operationinformation received by a step for receiving the operation information.

By devising the above method, the zoom rate is automatically changed inthe course of the scroll operation, and the zoom rate control isprevented from suffering from a frequent change due to the change of thescroll speed. Further, various features of the screen display apparatusof the present invention can be applied to the method for displaying thescreen of the present invention.

In the present invention, a program stored in a memory medium foroperating a computer as a screen display apparatus includes steps ofreceiving operation information regarding the scroll direction and thescroll speed from the input device, and performing the zoom process forchanging the zoom rate based on the scroll time and the scroll speed inthe same direction with performing the scroll process for scrolling acontent of a screen based on the operation information received by astep of receiving the operation information.

By devising the above program, the zoom rate is automatically changed inthe course of the scroll operation, and the zoom rate control isprevented from suffering from a frequent change due to the change of thescroll speed. Further, various features of the screen display apparatusof the present invention can be applied to the program for displayingthe screen of the present invention.

In another aspect of the present invention, the screen display apparatusincludes a touch panel that senses a touch position of a finger in thescreen, and a screen controller that performs a scroll process forscrolling the content of the screen based on the touch position andperforms the zoom process for zooming out control of the content of thescreen in the course of scrolling when a continuous touch of the fingerfor a predetermined period is detected.

When the finger is touching the touch panel continuously for thepredetermined period as described above, the zoom process for zoomingout and the scroll process are performed to quickly scroll through theinformation space based on the assumption that the user has an intentionthat he/she desires to get information far apart from a currentposition.

In yet another aspect of the present invention, the screen displayapparatus includes a touch panel that senses a touch position of afinger in a screen, a screen controller that operates in a first modeand in a second mode, and a switch unit that switches the first mode andthe second mode. In this case, the first mode of the screen controllerperforms a scroll process for scrolling a content of the screen based onthe touch position and performs a zoom process for zooming out controlof the content of the screen in a course of scrolling when a continuoustouch of the finger for a predetermined period is detected, and thesecond mode of the screen controller performs only the scroll processfor scrolling the content of the screen regardless of the period of thetouch of the finger.

When the first mode for simultaneous zoom out with scroll process andthe second mode for scroll only process are selectively provided, anappropriate scroll process is performed based on the intention of theuser. Also, the continuous touch of the user finger on the touch panelenables the user to scroll through the information space quickly bycombining the zoom out process with the scroll process according to theintention of the user.

In yet another aspect of the present invention, the screen displayapparatus includes a coordinate input unit that detects the touchposition of one of the finger and the pointing device by using a flatdetection device, a screen controller that performs a scroll process forscrolling a content of the screen based on the touch position andperforms the zoom process for zooming out control of the content of thescreen in the course of scrolling when the continuous touch of thefinger for a predetermined period is detected and a switch unit thatswitches an operation mode between the first mode and the second mode.

When the finger is touching the coordinate input unit continuously forthe predetermined time, the zoom process for zooming out and the scrollprocess are performed to quickly scroll through the information spacebased on the assumption that the user has an intention that he/shedesires to get information far apart from a current position.

In still yet another aspect of the present invention, the screen displayapparatus includes a joystick that senses an inclination direction andan inclination angle of itself, and a screen controller that performs ascroll process for scrolling a content of a screen based on theinclination direction and the inclination angle of the joystick andperforms a zoom process for changing a zoom rate of the content of thescreen based on a scroll time and a scroll speed of scrolling in a samescroll direction.

In this manner, the scrolling controlled by the joystick is also enabledto have the automatic zoom rate change capability according to thescroll direction and the scroll speed. In this case, the screencontroller may determine the scroll direction according to theinclination direction of the joystick, and may determine the scrollspeed according to the inclination angle of the joystick.

In still yet another aspect of the present invention, the screen displayapparatus includes a rotary input device that senses a rotationdirection and a rotation speed, and a screen controller that performsthe scroll process for scrolling the content of the screen based on therotation direction and the rotation speed and performs the zoom processfor changing the zoom rate of the content of the screen based on thescroll time and the scroll speed of scrolling in the same scrolldirection.

In this manner, the scrolling controlled by the rotary input device isalso enabled to have the automatic zoom rate change capability accordingto the scroll direction and the scroll speed. In this case, the rotaryinput device may be, for example, a trackball, a jog dial, a rotary knob(e.g., a device such as a volume control knob of an audio apparatus).

The screen controller may determine the scroll direction according tothe inclination direction of the joystick, and may determine the scrollspeed according to the inclination angle of the joystick.

In still yet another aspect of the present invention, a program storedin a memory medium for operating a computer as a screen displayapparatus comprising steps of receiving position information regarding atouch position of a finger from a touch panel, and a step of performinga zoom process for a zooming-out with scrolling control of a content ofa screen based on a detection of a continuous finger contact for apredetermined period simultaneously with performing a scroll process forscrolling the content of the screen based on the touch position of thefinger.

By executing this program, the continuous touch of the finger on thetouch panel is associated with the zoom out with scroll process, therebyenabling the user to quickly scroll through the information space basedon the intention of the user.

The present invention provides an outstanding advantage that the zoomrate is automatically changed in association with the scroll operation,and the zoom rate is controlled with ease based on the prohibition ofthe frequent zoom rate change due to the change in the scroll speed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a block diagram of a screen display apparatus according toa first embodiment of the present invention;

FIG. 2 shows an illustration of a joystick;

FIG. 3 shows an illustration that depicts a relationship of a joysticklever movable range and a threshold for zooming operation;

FIG. 4 shows a flowchart of an operation process of the screen displayapparatus in the first embodiment;

FIG. 5 shows a block diagram of a screen display apparatus in a secondembodiment of the present invention;

FIG. 6 shows an illustration that depicts a principle for calculating azoom decision value;

FIG. 7 shows a flowchart of an operation process of the screen displayapparatus in the second embodiment;

FIG. 8 shows map information stored in a map information storage in athird embodiment of the present invention;

FIG. 9 shows a block diagram of a car navigation system in a fourthembodiment of the present disclosure;

FIG. 10 shows an illustration of the screen display apparatus that isequipped with a touch panel;

FIG. 11 shows a flowchart of a scroll control in a fourth embodiment ofthe present invention;

FIG. 12 shows an illustration of a zoomed-in area shown on a content ofa screen at current zoom rate;

FIG. 13 shows a flowchart of a scroll control in a fifth embodiment ofthe present invention;

FIG. 14 shows a flowchart of a scroll control in a sixth embodiment ofthe present invention;

FIG. 15 shows a flowchart of a scroll control in a seventh embodiment ofthe present invention;

FIG. 16 shows a flowchart of a scroll control in a eighth embodiment ofthe present invention; and

FIG. 17 shows a block diagram of the screen display apparatus in a ninthembodiment of the present invention.

DETAILED DESCRIPTION

Embodiments of a screen display apparatus of the present invention isdescribed with reference to the drawing. In the following, the screendisplay apparatus is described as a map image display apparatus.However, application of the present invention is not limited to the mapimage display apparatus.

(First Embodiment)

FIG. 1 is a block diagram showing a constitution of a screen displaydevice 1 in a first enforcement. The screen display device 1 includes anoperation information receiver 10 for receiving an operation informationfrom a joystick 20, an image controller 12 for controlling a content ofa screen based on the operation information received by the operationinformation receiver 10, a RAM 14 for storing the operation informationreceived by the operation information receiver 10, and a display 16 fordisplaying the content of the screen under control of the imagecontroller 12.

FIG. 2 is an illustration showing an appearance of the joystick 20. Thejoystick 20 includes a lever 22 which can be inclined in eitherdirection on a stand part 26. The joystick 20 transmits a signal thatrepresents an inclination direction and an inclination angle of thelever 22, i.e., the operation information, to the screen display device1. Plural switches 24 are disposed at an upper part of the lever 22 ofthe joystick 20. In addition, plural switches 28 are disposed on thestand part 26 that supports the lever 22. The joystick 20 may transmit asignal to the screen display device 1 showing that the switch 24, 28 orthe like are pushed.

The image controller 12 of the screen display device 1 has a functionfor controlling a scroll of the content of the screen based on theinclination direction and the inclination angle of the joystick 20received by the information receiver 10. More practically, the imagecontroller 12 displays map information on the screen in a successivelychanging manner so that the image on the screen appears to be scrollingor zooming after retrieving the map information from map informationstorage 18.

The image controller 12 controls the scroll of the content of the screenin the inclination direction of the joystick 20 at a speed that accordswith the inclination angle based on the operation information receivedfrom the joystick 20.

Further, the image controller 12 controls the zoom rate based on theinputted operation information as well as the past operation informationstored in the RAM14. Concretely, when the joystick 20 is detected to beinclining in the same direction continuously for a prescribed time to anextent that is greater than a threshold D1, the image controller 12performs a zoom out process. At the time of zooming out, the imagecontroller 12 performs the zoom out process at a constant speed so thatthe zooming out looks smooth. In this case, an upper boundary of thezooming out is set in advance, and the zoom out process stops when thezoom rate reaches the upper boundary.

Furthermore, at a zoomed out condition, when the joystick 20 is detectedto be inclined in the same direction continuously for a prescribed timeto an extent that is equal to or smaller than a threshold D2 that issmaller than the threshold D1, the image controller 12 performs a zoomin process. At the time of zooming in, the image controller 12 performsthe zoom in process at a constant speed so that the zooming in lookssmooth. In this case, a lower boundary of zooming in is set in advancein the present embodiment, and the zoom in process stops when the zoomrate reaches the lower boundary. In the present embodiment, the lowerboundary of the zoom rate is the zoom rate that is used to display thecontent of the screen for the first time with the zoom rate displayedtherein (i.e., a “default” content of the screen). Therefore, the imagecontroller 12 does not perform the zoom in process if the content of thescreen is not in a zoomed out condition from the default.

FIG. 3 is an illustration of a relationship between an operable range ofthe lever 22 of the joystick 20 and the thresholds D1, D2. A verticalaxis of a diagram in FIG. 3 and a horizontal axis of the samerespectively show the inclination angle of the lever 22 in alongitudinal direction and a lateral direction. When the inclinationangle of the joystick 20 is greater than the threshold D1, the zoom outprocess is performed. That is, when the lever 22 of the joystick 20 isinclined within an area A3 in the diagram of FIG. 3, the zoom outprocess is performed. When a degree of the inclination angle of thejoystick 20 is equal to or smaller than the threshold D2, the zoom inprocess is performed. That is, when the lever 22 of the joystick 20 isinclined within an area A1 in the diagram of FIG. 3, the zoom in processis performed. Further, a degree of the inclination angle of the joystick20 is within an area A2, the inclination angle is neutral for a changeof the zoom rate. That is, the image controller 12 does not perform aprocess to change the zoom rate. In this manner, the image controller 12performs the zoom out process when the joystick 20 is largely inclinedin a certain direction, and the image controller 12 performs the zoom inprocess when the inclination angle of the joystick 20 decreases to acertain range. Therefore, the content of the screen is controlledaccording to the intention of the user.

FIG. 4 shows a flowchart of an operation process of the screen displaydevice 1 in the present embodiment. The screen display device 1 receivesthe operation information transmitted from the joystick 20 one by oneand performs a screen display control based on the operationinformation. In the following, the operation process of the screendisplay device 1 is described.

The screen display device 1 in the present embodiment receives theoperation information that represents the inclination direction of thelever 22 and the degree of the inclination angle from the joystick 20(S10). The screen display device 1 inputs the operation informationreceived by the operation information receiver 10 to the imagecontroller 12, and the image controller 12 stores the inputted operationinformation in the RAM14 temporarily (S12).

Image controller 12 determines a degree of the inclination angle of thejoystick 20 based on the inputted operation information (S14). Based ona result of the determination of the inclination angle, when the degreeof the inclination angle of the joystick 20 is equal to or less than thethreshold D2 (included in the area A1 of FIG. 3), the image controller12 performs the following process. First, the image controller 12determines whether the angle is equal to or less than the threshold D2for more than predetermined time (S16).

When the inclination angle equal to or under the threshold D2 is notkept for more than the predetermined time as a result of thedetermination (S16:NO), the image controller 12 performs the scrollprocess based on the inputted operation information (S26). When theinclination angle equal to or under the threshold D2 is determined to bekept for more than the predetermined time (S16:YES), the imagecontroller 12 determines whether a current zoom rate is the maximum zoomrate (a default zoom rate) (S18).

When the current zoom rate is the maximum zoom rate as a result of thedetermination (S18:YES), the image controller 12 performs the scrollprocess (S26). When the current zoom rate is not the maximum zoom rate(S18:NO), the image controller 12 performs the zoom process with thescroll process based on the inputted operation information for scrollingthe content of the screen with zooming in (S20). Then, the screendisplay device 1 returns to step S10 for receiving the operationinformation from the joystick 20.

When the degree of the inclination angle of the joystick 20 is greaterthan the threshold D2 and equal to or less than the threshold D1 (withinthe area A2 of FIG. 3) as a result of determination of the inclinationangle of the joystick 20 (S14), the image controller 12 performs thefollowing process. First, the image controller 12 determines whether thezoom rate is being changed (S22). In other words, the image controller12 determines whether the zoom in process (S20) or the zoom out process(S32) is being performed.

When the zoom rate is determined to be changing as a result of thedetermination (S22:YES), the image controller 12 stops the zoom process(S24), and performs the scroll process based on the inputted operationinformation (S26). When the zoom rate is determined to be not changing(S22:NO) in the determination the zoom rate change condition (S22), theimage controller 12 performs the scroll process based on the inputtedoperation information (S26). Then, the screen display device 1 returnsto step S10 for receiving the operation information from the joystick20.

When the inclination angle is greater than the threshold D1 (i.e.,within the area A3 of FIG. 3) as a result of the determination of theinclination angle of the joystick 20 (S14), the image controller 12performs the following process. First, the image controller 12determines whether the inclination angle greater than the threshold D1in the same direction is kept for more than the predetermined time(S28).

When the inclination angle greater than the threshold D1 is determinednot to be kept for more than the predetermined time (S28:NO) as a resultof the above determination, the image controller 12 performs the scrollprocess based on the inputted operation information (S26). When theinclination angle greater than the threshold D1 is determined to be keptfor more than the predetermined time (S28:YES), the image controller 12determines whether the current zoom rate is the minimum zoom rate (S30).

When the current zoom rate is determined to be minimum as a result ofthe above determination (S30:YES), the image controller 12 performs thescroll operation based on input operation information (S26). When thecurrent zoom rate is determined to be not minimum as a result of theabove determination (S30:NO), the image controller 12 performs the zoomprocess with the scroll process based on the inputted operationinformation for scrolling the content of the screen with zooming out(S32). Then, the screen display device 1 returns to step S10 forreceiving the operation information from the joystick 20.

The configuration and operation of the screen display apparatus 1 in thefirst embodiment is described in the above.

The screen display device 1 in the first embodiment performs the zoomout process when the joystick 20 in inclined in the same direction forthe predetermined time over the threshold D1 (S30), and stops the zoomout process when the inclination angle is decreased equal to or belowthe threshold D1 (S24). In this manner, the content of the screen can bechanged to an arbitrary zoom rate, and can also be scrolled at aconstant zoom rate that is set at the time of static content display.Therefore, the large volume information can easily be searched only byan operation of the joystick 20 that changes the zoom rate with ease inthe course of scrolling. This feature in the present embodiment isespecially advantageous when the content of the screen such as the mapor the like is desired to be viewed in both of the zoomed in conditionand the zoomed out condition.

Further, the device 1 zooms out the content of the screen only when thejoystick 20 is inclined in the same direction continuously for thepredetermined time (S28). This operation seems to be performed only whenthe user has the intention that he/she desires to view the informationfar apart from the current position. That is, when the information issearched around the current position, the zoom rate is not changedagainst the intention of the user in the present embodiment, therebyenabling the user to search the information with ease.

(Second Embodiment)

FIG. 5 shows a block diagram of a screen display apparatus 2 in a secondembodiment of the present invention. The apparatus 2 has basically thesame structure as the apparatus 1 in the first embodiment. The apparatus2 includes a touch pad 30 instead of the joystick 20. In the secondembodiment, the image controller 12 controls the screen based on theoperation information transmitted from the touch pad 30. The operationcontrol by the image controller 12 in the second embodiment is describedin the following.

First, before describing the image controller 12, the touch pad 30 isdescribed. The touch pad 30 input information by sensing a trace by afinger on a pad. The present embodiment utilizes the touch pad 30 thatis pressure sensitive for sensing a movement of the finger by detectinga pressure on the pad. The touch pad 30 converts the position of thefinger detected by the pad to an input value. The touch pad 30 transmitsa signal (i.e., operation information) to the apparatus 2.

Now, the image controller 12 in the second embodiment is described. Theimage controller 12 has a function that scrolls the content of thescreen in a traced direction by the speed that accords with a tracespeed of the finger for tracing the pad.

Further, the image controller 12 controls the zoom rate based on theinputted operation information as well as the past operation informationstored in the RAM14. Concretely, when the touch pad 30 is repeatedlytraced in the same direction (“repeated input” in the following), theimage controller 12 performs the zoom out process. At the time ofzooming out, the image controller 12 performs the zoom out process at aconstant speed so that the zooming out looks smooth. In this case, theupper boundary of the zooming out is set in advance, and the zoom outprocess stops when the zoom rate reaches the upper boundary.

Furthermore, when the repeated input is not detected, the imagecontroller 12 performs the zoom in process. At the time of zooming in,the image controller 12 performs the zoom in process at a constant speedso that the zooming in looks smooth. In this case, the lower boundary ofzooming in is set in advance, and the zoom in process stops when thezoom rate reaches the lower boundary (i.e., the default rate).Therefore, the image controller 12 keeps the default zoom rate in thedefault condition if the repeated input is not detected.

Now, the determination of carrying out the zoom out process based on therepeated input is described. The image controller 12 controls the zoomout process based on a finger departure speed from the touch pad 30 anda cycle of the repeated input when the repeated input is detected. Inthe present embodiment, a paper plane model is used to calculate thezoom decision value. The decision value is described in detail in thefollowing.

FIG. 6 shows an illustration that depicts a principle for calculatingthe zoom decision value. The zoom decision value corresponds to a “liftforce” in the paper plane model. The image controller 12 calculates a“height” of a triangle with the finger departure speed defined as thebase of the triangle and the reciprocal of the cycle of the repeatedinput (i.e., the number of iteration per unit time) as the rotationangle (i.e., the angle for calculating a tangent). In this case, FIG. 6shows only a principle, and the actual value of the lift may becalculated appropriately by adding/multiplying a constant. As clearlyshown in FIG. 6, the zoom decision value increases when the cycle of therepeated input becomes shorter, or when the finger departure speedbecomes faster. When the finger departure speed is zero, or when theinput is not repeated, the zoom decision value is zero. The zoomdecision value calculated in this manner reflects the intention of theuser who desires to view the information far apart from the currentposition. As an analogy of the paper plane that the lift forcesurpassing the gravitation force lifts the paper plane, the imagecontroller 12 performs the zoom out process when the zoom decision value(the lift force) surpasses a predetermined threshold (the gravitationforce), and performs the zoom in process when the zoom decision value isequal to or smaller than the threshold. The screen display apparatus 2is configured to have an appropriate value as the predeterminedthreshold.

FIG. 7 shows a flowchart of an operation process of the screen displayapparatus 2 in the second embodiment. The screen display apparatus 2receives the operation information transmitted from the touch panel 30one by one, and performs the screen display control based on theoperation information. The operation of the screen display apparatusafter the reception of the operation information is described in thefollowing.

The screen display device 2 receives the operation information thatrepresent a traced direction and speed of the touch pad 30 from thetouch pad 30 (S40). Screen display device 2 inputs the operationinformation received by operation information receiver 10 to imagecontroller 12, and image controller 12 stores the inputted operationinformation in RAM14 temporarily (S42).

The image controller 12 of the screen display device 2 determineswhether the finger touched the touch pad 30 based on the operationinformation (S44). When a touch of the finger on touch pad 30 is notdetected (S44:NO), the finger has already touched the touch pad 30. Theimage controller 12 determines whether the finger has departed from thetouch pad 30 (S46). When the departure of the finger has not beendetected in this determination (S46:NO), the finger has been moved in astate of touching the touch pad 30. In this case the image controller 12scrolls the content of the screen in the traced direction at the speedthat accords with the trace speed on touch pad 30 (S60).

When the finger departure from the touch pad 30 is detected (S46:YES) inthe determination process (S46), the image controller 12 calculates thefinger departure speed (S48). The finger departure speed is a speed ofthe finger at a small period of time when the finger departs. Next, theimage controller 12 calculates the cycle of tracing on the pad 30 basedon the operation information stored in RAM14 (S50). When the repeatedinput is detected based on the operation information stored in RAM14,the image controller 12 calculates the cycle of the inputs as an averageof the period between finger departure times and finger landing times.When the repeated input is not detected, the image controller 12determines that the cycle is equal to “∞” (an infinite: the number ofiteration per unit time=0).

The image controller 12 determines the zoom decision value based on thecycle of the traces on the pad 30 and the finger departure speed, andperforms the zoom out process when the zoom decision value is greaterthan the predetermined threshold, or performs the zoom in process whenthe value is equal to or smaller than the threshold (S52). When therepeated is not detected, the zoom decision value becomes 0 and theimage controller 12 performs the zoom in process. However, when thecontent of the screen is displayed by the default zoom rate, and thezoom rate is kept as it is because further zooming in is not performed.Then, the image controller 12 returns to step S40 for receiving theoperation information from the touch pad 30.

When, in the determination of the touch of the finger on the touch pad30 (S44), the touch of the finger is detected (S44:YES), the imagecontroller 12 determines whether the speed of the finger at the time oflanding on the touch pad is equal to zero (S54). The finger landingspeed is a speed of the finger at a small period of time when the fingerlands on the pad 30. In this case, though the process (S54) determineswhether the speed is equal to zero or not, the speed may be determinedto be equal to zero by the image controller 12 even when the speed isnot accurately equal to zero. The range of the values to be determinedas zero may be arbitrarily set according to the sensitivity of the touchpad or the like.

When the finger landing speed is not determined to be equal to zero inthis determination (S54:NO), the image controller 12 performs the scrollprocess in the traced direction at the speed that accords with the tracespeed (S60).

The image controller 12 determines whether the zoom process is beingperformed (S56) when the speed of finger landing is determined to beequal to zero (S54:YES). That is, the image controller 12 determineswhether the zoom rate change (S52) is performed. The image controller 12stops the zoom rate change (S58) and performs the scroll process in thetraced direction of the touch pad 30 at the speed that accords with thetrace speed (S60) when the zoom rate change is determined to beperformed as a result of the determination (S56:YES). When the zoom ratechange is determined to be not performed as a result of thedetermination (S56:NO), the image controller 12 performs the scrollprocess in the traced direction of the touch pad 30 at the speed thataccords with the trace speed (S60). Then, the image controller 12returns to step S40 for receiving the operation information from thetouch pad 30.

The configuration and the operation of the screen display apparatus 2 inthe second embodiment of the present invention are described in theabove.

The screen display apparatus 2 in the present embodiment performs thezoom out process when the zoom decision value surpasses thepredetermined threshold based on the cycle of the repeated input and thefinger departure speed, and zooms out until the finger touches the touchpad 30 at the trace speed of zero. Therefore, the content of the screencan be arbitrary zoom rate only by tracing the touch pad 30.

In the screen display apparatus 2 of the present embodiment, the zoomdecision value increases as the cycle of the repeated input decreases,and as the finger departure speed increases. Repeated tracing operationin the same direction is performed under the intention to scroll in thetraced direction in large. Therefore, the apparatus 2 prevents anunwanted zoom rate change in the search operation for searching theinformation at the proximity of the current viewing position of theinformation and makes the information search easier, when the apparatus2 is configured to performs the zoom out process only with the zoomdecision value surpassing the predetermined threshold.

The screen display apparatus 2 calculates the zoom decision value forperforming the zooming out of the content of the screen, that is, fordetermining whether the user plans to view the information far apart,based on the finger departure speed from the touch pad 30. The conditionof the finger departure having a certain departure speed may becomparable to the condition of throwing a paper when the screen isregarded as a piece of paper. Therefore, the interface provided in thepresent invention enables the user to reflect the feeling of the user tothe scrolling operation of the content of the screen.

The screen display apparatus 2 in the present embodiment stops the zoomrate change process when the finger landing speed on the touch pad 30 iszero (S54:YES). The operation of tracing the touch pad 30 with the speedof zero may be assumed to be analogous to the operation that touches thecontent of the screen under the zoom rate change control with pressingdown force applied thereto. Therefore, when the content of the screen isconsidered as a piece of paper, the zoom rate change may be stopped byan operation causing a similar feeling of pressing down the piece ofpaper. In addition, the pad 30 may be traced without lifting the fingerfrom its surface for scrolling the content without changing the zoomrate, thereby providing an interface that suits to the feeling of theuser.

Though the present embodiment utilizes the touch pad as an example ofthe input device, a touch panel that integrally includes a fingerdetection device and a display screen may also be utilized forcontrolling the content of the screen as described in the presentembodiment. Further, an input device other than the touch panel may alsobe used as long as the input device is a flat coordinate input devicefor detecting a touch position of the finger or the pointing device.

(Third Embodiment)

A third embodiment of the present invention has a screen displayapparatus 3 that is configured basically in the same manner as theapparatus 1 of the first embodiment (shown in FIG. 1), with a differentfeature of adsorption points 40 stored in the map data. The adsorptionpoints 40 are the points that define a position of centering of thescreen when the zoom in process is performed.

FIG. 8 shows map information stored in a map information storage 18 inthe third embodiment of the present invention. The map informationstorage 18 stores plural adsorption points 40 defined on a map of UnitedStates of America.

When zooming in of the screen that includes the adsorption point 40 isperformed, the screen of the screen display apparatus 3 is centeredaround the adsorption point 40 in the third embodiment. When pluraladsorption point 40 is included in the screen being zoomed out, thescreen is centered around the adsorption point 40 that is nearest to thecenter of the screen.

Because the adsorption point 40 comes to the center of the screen tosave a tactful manual centering operation of the point 40 in the zoom inprocess of the third embodiment, the interface of the screen displayapparatus becomes very convenient for the user. For example, by settinghighly referenced points such as an urban region, a station or the likeas the adsorption points 40, the zoomed out screen can be easilycentered around those highly referenced points.

Further, though the apparatus 3 in the third embodiment has basicallythe same structure as the apparatus 1 in the first embodiment, theadsorption points 40 in the present invention may also be applicable tothe apparatus 2 in the second embodiment that includes the touch pad 30.

(Fourth Embodiment)

FIG. 9 shows a block diagram of a car navigation system 50 with a screendisplay apparatus in a fourth embodiment of the present invention.

In FIG. 9, the car navigation system 50 includes a position sensingdevice 52, a map data input unit 54, operation switches 56, atransceiver 58, an external memory 60, a display 62, a sound controller64, a speaker 66, a voice recognizer 68, a microphone 70, a remotecontroller sensor 72, a remote commander 74 and a control unit 76 whicheach of these devices are connected to.

The control unit 76 consists of it as a normal computer. Inside of thecontrol unit 76, a CPU, a ROM, a RAM, an input/output (I/O) and a busfor connecting these components are included. The control unit 76carries out predetermined processing (processing, for example, to changeof a map scale, menu indication choice processing, destination settingprocessing, route search execution processing, route guidance startprocessing, present position correction processing, screen changeprocessing, volume adjustment processing and the like) based on variousinformation input from the position sensing device 52, the map datainput unit 54; the operation switches 56, the transceiver 58, theexternal memory 60, the sound controller 64, the remote controllersensor 72.

The position sensing device 52 has a geomagnetism sensor 80, a gyroscope82, a distance sensor 84 and a Global Positioning System (GPS) receiver86. The GPS receiver 86 has a function to detect a vehicle positionbased on an electric wave from a satellite. Because of errors ofdifferent nature, each sensor included in the position sensing device 52is configured to compensate the errors with each other. In addition, arotation sensor of a steering wheel, a tire sensor of each tire or thelike may be used as the position sensing device 52. Further, based on anaccuracy of position sensing, the position sensing device 52 may includepart of the sensors of described above.

The map data input unit 54 with a memory medium is a device to inputvarious data including data for so-called map matching for precisionimprovement of position sensing stored in the memory medium, map dataand mark data. Though it is common to use a CD-ROM or a DVD-ROM whichcan record large-volume information as the storage medium, the memorymedium may be a memory card, an HDD or the like.

Operation switches 56 have the touch panel that is integrally structuredwith the display 62 as well as the mechanical switches such as a powerbutton or the like. The touch panel detects a contact position of afinger on the screen and transmits the detected information to thecontrol unit 76. The operation switch 56 transmits operationinstructions of various functions (for example, a map scale change, menuindication choice, destination setting, a route search, roué guidance, acurrent position correction, an screen change, volume adjustment and thelike) to the control unit 76 based on switch operation. In addition,though, in the present embodiment, the explanation is focused on thetouch panel that detect a contact of the finger, it is apparent that useof the touch panel to detect instruction positions with an instructiondevice such as a stylus pen or the like may also be acceptable, and theuse of the instruction device such as a stylus is included in theembodiment of the present invention.

The remote commander 74 includes plural operation switches (not shown inthe figure). The remote commander 74 inputs information of switchoperation into the control unit 76 through remote controller sensor 72.The control unit 76 carries out various functions depending on theswitch operation. In addition, operation switches 56 and the remotecommander 74 can make the control unit 76 carry out the same function bythe switch operation of any kind.

When a destination is set with the remote commander 74 or operationswitches 56, the control unit 76 searches an optimum route from thecurrent vehicle position detected by position sensing device 52 to thedestination, and displays the route on the display 62. As the techniqueto automatically set the optimum route, Dijkstra method or the like isknown.

The display 62 displays a map or a destination choice screen or thelike, and is capable of full color display. The display 62 may bestructured by using a liquid crystal, an organic electroluminescence orthe like. The display 62 displays a map based on information of the mapdata input unit 54, and an optimum route to the destination on the mapin a superposing manner. In addition, the display 62 displays a currentposition mark detected by the position sensing device 52 to display acurrent vehicle position on the map. Further, the display 62 can alsodisplay other information such as a current time, traffic jaminformation additionally beside the current position, the route.

The external memory 60 is writable mass storage such as a HDD or thelike. The external memory 60 stores a large quantity of data and thedata which must not be erased even when the power supply is turned OFF,and the memory 60 may also be used to retain a copy of frequently useddata from the map data input unit 54. In this case, the external memory60 may be a comparatively small memory that can be removable from asystem.

The transceiver 58 has a function to receive information from outside(for example, infrastructure such as VICS systems in Japan) such astraffic information, weather information, facility information,advertising information and the like, and has a function to sendinformation such as vehicle information, user information and the liketo the outside. The transceiver 58 transmits the information receivedfrom the outside to the control unit 76, and the information isprocessed by the control unit 76. In addition, the transceiver 58 canoutput the information that is processed by the control unit 76 ifnecessary from transceiver 58 itself.

The speaker 66 outputs audible signals such as a guidance voice, ascreen operation instruction, a voice recognition result and the likebased on a voice output signal input from the sound controller 64.

The microphone 70 inputs voice of the user as an electric signal to thevoice recognizer 68.

The voice recognizer 68 compares an input of the voice of the user fromthe microphone 70 and vocabulary data (i.e., comparison patterns) in arecognition dictionary stored therein, and inputs a most matching datato the sound controller 64.

The sound controller 64 controls the voice recognizer 68, and controls atalkback output control (i.e., an audio output) through the speaker 66.In addition, the sound controller 64 controls to input a recognitionresult of the voice recognizer 68 into the control unit 76. The controlunit 76 carries out a predetermined processing (processing, for example,to change of a map scale, menu indication choice processing, destinationsetting processing, route search execution processing, route guidancestart processing, present position correction processing, screen changeprocessing, volume adjustment processing and the like) in response forutterance of the user based on the information from the voice recognizer68. In addition, route guidance sound information processed by thecontrol unit 76 and the like is provided through the sound controller 64from speaker 66.

Then, the scroll process of the screen displayed on the display 62 isdescribed. FIG. 10 shows an illustration of an example of the display 62with the touch panel that shows an image. As shown in FIG. 10, thescreen shown in the display 62 always displays the image around an areaC (a ‘center area’ hereinafter) that includes a center portion of thedisplay 62, and also displays an area E (a ‘peripheral area’hereinafter) that includes a peripheral portion of the display 62 withan exclusion of the center area in a half transparent manner. In thismanner, the' user can easily distinguish the center area C from theperipheral area E.

In the present embodiment, the control unit 76 performs scroll with zoomwhen the peripheral area E with semi-transparency is touched, and thecontrol unit 76 performs scroll without zoom when the center area C istouched. In the following description, the scroll with zoom isdesignated as “the first mode” and the scroll without zoom is designatedas “the second mode.”

FIG. 11 shows a flowchart of a scroll control in a fourth embodiment ofthe present disclosure. When the touch panel detects the contact of thefinger (S70), the control unit 76 determines whether the position of thecontact is in the peripheral area E (S72). When the position of thecontact is in the peripheral area E (S72:YES), the control unit 76controls the screen in the first mode.

In the first mode, the control unit 76 determines whether the time oftouching on the touch panel is longer than a preset time (S90). Whentime of touching does not surpass the preset time (S90:NO), the displayunit 62 performs the scroll process according to the touch position. Forexample, the scroll process is conducted in a direction that isdetermined by a vector form the center of the screen to the touchposition. In this case, the scroll speed may be determined depending onthe distance from the center of the screen to the touch position. Thecontrol unit 76 determines whether the finger has departed from thetouch panel while performing the scroll process (S94). When the fingeris determined to depart (S94:YES), the screen control is concluded. Inother words, the control unit 76 stops the scroll process and displays amap at a stopped position.

When the finger is determined not to depart (S94:NO), the processreturns to step S90 and determines whether the preset time of touchinghas passed (S90). With this control, the scroll without zoom isperformed till the preset touching time passes, and, a process forstopping the screen control is performed at the time of the fingerdeparture (S94:YES).

When the touching time has passed the preset time (S90:YES), the controlunit 76 performs the scroll process according to the touch positionaccompanied by the zoom out process (S96). In this case, the scrollspeed may be a constant speed without regard to the zoom rate, or may bedecreased in proportion to the decrease of the zoom rate. When the zoomrate becomes smaller, a wider area is displayed in the screen. By makingthe scroll speed slower, the position of the scroll can be fine-tuned inthe map that displays the wider area.

The control unit 76 determines whether the finger has departed from thetouch panel while performing the scroll process and the zoom out process(S98). When the finger has not determined to depart (S98:NO), the zoomout process and the scroll process are continued. In this case, the zoomout process stops when it reaches the minimum zoom rate of a presetvalue, and only the scroll process is continued at the preset minimumzoom rate afterwards.

When the finger has determined to depart (S98:YES), the control unit 76calculates the area that is displayed in the screen at the time of thezoom in to the maximum zoom rate, and displays the calculated area onthe image at the current zoom rate (S100).

FIG. 12 shows an illustration of a zoomed-in area shown on the contentof the screen at the current zoom rate. As shown in FIG. 12, theposition of the zoomed-in area in the wide area map can be grasped asthe zoomed-in area T on the map of the current zoom rate. In this case,though the zoomed-in area T is described in the present embodiment, thezoom in process may simply be performed without displaying the area T.

Then, the control unit 76 performs the zoom in process (S102) to returnto the maximum zoom rate. In this case, in step S102 in FIG. 11, thezoom in process only is performed after the finger departure. However,the scroll with the zoom in process may be performed according to thefinger position at the time of the finger departure. In this case, thecalculation of the zoomed-in area displayed in step S100 takes into theaccount the gap of the display area caused by the scroll. Theabove-described process is the screen control in the first mode.

In the determination that the touched position is in the peripheral areaE (S72), the control unit 76 performs the scroll process according tothe touched position (S104) when the touched position is not determinedto be the peripheral area E (S72:NO). The control unit 76 determineswhether the finger has departed from the touch panel (S106) whileperforming the scroll process. When the finger has not determined todepart (S106:NO), the scroll process is continued, and the finger hasdetermined to depart (S106:YES), the screen control is concluded. Thatis, the control unit 76 stops the scroll process and displays the map atthe stopped position.

The above is the description of the navigation system 50 that isequipped with the screen display apparatus in the fourth embodiment ofthe present disclosure.

The screen display apparatus in the present embodiment performs thescroll without zoom when the center area C of the touch panel istouched, and performs the scroll with zoom when the peripheral area E ofthe touch panel is touched. When the user touches the peripheral area E,it indicates that the user is considered to have an intention to see theadjacent area next to the display area in the screen, or the areafarther than the adjacent area. In the present embodiment, by the zoomout process at the touch of the peripheral area E, the intention of theuser is reflected to a fast scroll in the information space.

Further, because the screen display apparatus in the present embodimentperforms the zoom out process after the preset time from the touch ofthe peripheral area E, the zoom out process is not performed when theperipheral area E is mistakenly touched. By performing the scrollwithout zoom before the preset time passes, the intention of the user totouch the peripheral area E is undoubtedly assumed to appropriatelyperform the zoom out process. In addition, the user needs not besurprised by a start of the zoom out process.

Because the display 62 displays the peripheral area E withsemi-transparency and displays the center area C as normal transparencyin the screen in the present embodiment, the user can grasp where theperipheral area E is in the screen. In this case, the peripheral area Emay be separated from the center area C by a line instead of beingdisplayed with semi-transparency for the purpose of easy recognitionfrom the center area C in the present embodiment. In addition, theperipheral area E may not be distinguished from the center area C in thescreen.

(Fifth Embodiment)

In the navigation system in a fifth embodiment is described in thefollowing. The navigation system in the present embodiment is basicallythe same as the one in the fourth embodiment (refer to FIG. 10), withthe difference of a mode switch method that switches the operation modeof the system between the first mode and the second mode.

FIG. 13 is a FIG. 13 shows a flowchart of a scroll control in the fifthembodiment of the present invention. The touch panel determines whethertwo or more places are touched at the same time on the screen (S74),when the touch on the screen is detected (S70). When more than twoplaces are determined to be touched at the same time (S74:YES), thecontrol department 76 performs a screen control (scroll with zoom) bythe first mode, and when more than two places are not determined to betouched at the same time (S74:NO), the control department 76 performs ascreen control (scroll without zoom) by the second mode. The first modeand the second mode of the screen control are the same as the screencontrol of the fourth embodiment.

The screen display apparatus in the fifth embodiment can switch thescroll of the screen with/without zooming by the number of touchingfingers on the touch panel. Therefore, the user can switch the operationmode only by operating the touch panel.

The present embodiment may be modified to a form that, when one fingeris detected to depart from the touch panel in the zooming out process ofthe first mode, the zooming out process is stopped to have the screenscrolled at the constant zoom rate at the time of the stop of thezooming out.

(Sixth Embodiment)

The navigation system equipped with the screen display apparatus in asixth embodiment of the present disclosure is described. The navigationsystem in the sixth embodiment is configured basically in the samemanner as the navigation system 50 in the fourth embodiment (refer toFIG. 10), and the touch panel in the sixth embodiment has a pressuresensing function when it detects the contact of the finger. Further, themethod of switching between the first and the second mode in the sixthembodiment is configured differently from the fourth embodiment.

FIG. 14 shows a flowchart of a scroll method in the sixth embodiment.The touch panel determines whether a press force of a touch is biggerthan the predetermined threshold (S76) when it detects a touch of ascreen (S70). When it is determined that the press force is equal to orsmaller than the predetermined threshold (S76:NO), the control unit 76controls the screen in the second mode. When it is determined that thepress force is greater than the predetermined threshold (S76:YES), thecontrol unit 76 controls the screen in the first mode. In the presentembodiment, being in the first mode is announced to the user beforeperforming the screen control in the first mode (S78). For example, avoice message such as “scroll with zooming” may be output, or anelectrical sound may bleep. In this manner, the user is notified thatthe scroll is performed in the preferred mode. In the presentembodiment, the description explains an example that the operation inthe first mode is notified when the first mode is set. However, thesecond mode may be notified when the operation is set to the secondmode, or both of the first and second mode may be notified when theoperation is set to either of the two modes. The screen control in thefirst mode and in the second mode thereafter is performed in the samemanner as the fourth embodiment.

The screen display apparatus in the sixth embodiment can switch whetherthe scroll is performed with or without zooming depending on the pressforce of the touch on the touch panel. Therefore, the user can switchthe operation modes only by operating the touch panel.

Further, in the present embodiment, the description explains an examplethat the screen control concludes itself for terminating each of theoperation mode when the touch of the finger is detected(S94/S98/S106:YES). However, the first and the second mode may beswitched with each other when the press force is varied with the fingerstaying in contact with the touch panel.

(Seventh Embodiment)

The navigation system equipped with the screen display apparatus in aseventh embodiment of the present disclosure is described. Thenavigation system in the seventh embodiment is configured basically inthe same manner as the navigation system 50 in the fourth embodiment(refer to FIG. 10). However, the method of switching between the firstand the second modes is configured differently.

FIG. 15 shows a flowchart of a scroll method in the seventh embodiment.When the touch of the screen is detected (S70), the touch panel traces amovement of the touching finger, and determines whether the length ofthe finger movement is longer than a predetermined threshold (S82). Whenthe length of the finger movement is longer than the threshold(S82:YES), the control unit 76 performs the screen control in the firstmode. When the screen control is in the first mode, being in the firstmode is notified for the user (S84) in the same manner as the sixthembodiment. When the length of the finger movement is smaller than thepredetermined threshold (S82:NO), the control unit 76 performs thescreen control in the second mode. The screen control in the first andthe second mode thereafter is performed in the same manner as the fourthembodiment.

The screen display apparatus in the seventh embodiment can switchwhether the scroll is performed with or without zooming with themovement of the finger, thereby enabling the user to switch theoperation mode only by operating the touch panel.

(Eighth Embodiment)

The navigation system equipped with the screen display apparatus in theeighth embodiment is described in the following. The navigation systemin the eighth embodiment is configured basically in the same manner asthe navigation system 50 in the fourth embodiment (refer to FIG. 10),with an addition of a mode switching switch in the operation switches 56for switching the operation mode. The mode switching switch may be, forexample, disposed on a steering wheel.

FIG. 16 shows a flowchart of a scroll control in the eighth embodiment.The touch panel determines the mode switching switch is set to which ofthe first and the second mode (S86) when the touch of the screen isdetected (S70). The control unit 76 performs the screen control ineither of the first or the second mode according to the setting of themode switching switch. The screen control in the first and the secondmode is performed in the same manner as the fourth embodiment.

As the screen display apparatus in the eighth embodiment can switchwhether the scroll with zooming is performed by using the mode switchingswitch, thereby allowing the user to easily and securely perform themode change.

(Ninth Embodiment)

FIG. 17 shows a block diagram of a screen display apparatus 90 in aninth embodiment of the present disclosure. The screen display apparatus90 in the ninth embodiment is configured basically in the same manner asthe screen display apparatus 1 in the first embodiment, with an additionof a reaction unit 92 that applies a reaction force to the movement ofthe joystick 20.

The screen display apparatus 90 in the ninth embodiment performs thescroll without zooming in the same manner as the apparatus 1 in thefirst embodiment when a inclination angle of the joystick 20 is equal toor smaller than the first threshold D1, and, performs the scroll withzooming when the inclination angle is greater than the first thresholdD1. Further, the apparatus 90 performs the zoom in process when theinclination angle of the joystick 20 became smaller than the secondthreshold D2 during the scroll with zooming.

In the screen display apparatus 90 of the ninth embodiment, the reactionunit 92 applies the reaction force to the joystick 20 in a directionthat suppresses the inclination angle to be equal to or smaller than thefirst threshold D1 when the joystick 20 is forced to be inclined to adegree that is greater than the first threshold D1. Further, thereaction unit 92 applies the reaction force to the joystick 20 in adirection that increases the inclination angle to be equal to or greaterthan the second threshold D2 when the inclination angle of the joystick20 is forced to be smaller than the second threshold D2.

When the inclination angle of the joystick 20 is forced to exceed thefirst threshold D1 or the second threshold D2, the screen displayapparatus 90 in the ninth embodiment applies the reaction force torestrict the original movement for the purpose of notification to theuser. In this manner, the user recognizes in a tactile manner that thezoom out process or the zoom in process will be started when the usermoves the joystick 20 against the reaction force.

Although the present invention has been fully described in connectionwith the preferred embodiment thereof with reference to the accompanyingdrawings, it is to be noted that various changes and modifications willbecome apparent to those skilled in the art.

The screen display apparatus 1, 2 described above may have a zoom stopbutton for stopping the zoom process. When the zoom rate is changed to acertain rate, the zoom rate is fixed by pressing the zoom stop button tohave the scroll performed without zooming. In this manner, the zoom ratewill not be automatically changed by any kind of operations, therebyproviding a confidence for the user that the scroll operation by theuser will be performed without zooming.

The screen display apparatus 1, 2 described above may not necessarilyperform the zooming operation at a constant zooming speed with thescreen controller 12, though the example described above adopts theconstant zoom speed. For example, the screen display apparatus 1 in thefirst embodiment may determine the zooming speed according to theinclination angle of the joystick 20. The apparatus 2 in the secondembodiment may determine the zooming speed in proportion to the zoomdecision value that is derived from the repeated input. However, ineither case, the zooming speed is controlled not to have a steep speedchange. In this manner, i.e., when the zooming speed is controlledaccording to the input value from the input device such as the joystick20, the touch pad 30 or the like, the zooming speed control according tothe intention of the user is achieved.

The screen display apparatus 2 in the second embodiment describes anexample that the zoom rate changing process is stopped when the speed ofthe finger that touches the touch pad 30 is equal to zero. However, twothreshold values may be set as those in the first embodiment, and thezoom decision value surpassing the first threshold value may cause thezoom out process and the zoom decision value equal to or smaller thanthe second threshold value may cause the zoom in process. In thismanner, the zoom rate changing process is stopped when the zoom decisionvalue stays equal to or under the first threshold and over the secondthreshold.

The screen display apparatus 2 in the second embodiment may control thezoom rate changing process based on the press force applied on the touchpad 30 by receiving the pressure signal that represents the press force.For example, a trace with a strong press force may cause the zooming outor the like.

The screen display apparatus 1 described above may have an anglechanging function for changing the angle of the map informationdisplayed in the screen, and may perform the zoom out and the zoom inprocess with the angle of the map being in a changed condition. Forexample, when the screen is in an angle that views the map in a lookingdown manner from a diagonal upper direction, the inclination angle ofthe joystick 20 over the predetermined threshold may cause the angle ofthe screen to be smoothly changed to the view of a straight looking-downfrom above while the view is being zoomed out.

Though the embodiment described above describes an example that uses thejoystick, the touch pad and the touch panel as the input devices, thepresent invention may be applicable to the input devices that is notdescribed in the embodiments. That is, for example, the screen displayapparatus of the present disclosure may be controlled based on theoperation information transmitted from a pointing device such as amouse, a jog-dial, a trackball, a rotary switch or the like. Thejog-dial is an input device that instructs operations by a rotation ofthe dial and a press of the dial. When the jog-dial is used, the screenmay be scrolled according to the rotation of the jog-dial, and the pressof the dial may be associated to the switching operation that switchesbetween the scroll with zooming and the scroll without zooming.

The touch panel described in the fourth to the eighth embodiments may bereplaced with the touch pad. Further, tee touch panel may be replacedwith other input devices as long as input device is the plane coordinateinput device that senses the touch position of the finger or thepointing device.

Though the example in the ninth embodiment described above applies thereaction force to the joystick 20 when the inclination angle of thejoystick 20 is the threshold of the zoom rate change, the reaction forceapplication condition is not limited to the zoom rate change.

Though the example in the ninth embodiment described above applies thereaction force to the user through the joystick 20, the application ofthe reaction force is not limited through the joystick 20. For example,the trackball, the jog-dial, and the rotary input device such as therotary switch or the like may have the reaction force that restricts therotation when the zoom rate is changed.

For example, the scroll through the boundaries of the municipalities mayhave the reaction force. In this manner, the user can easily recognizesthat the contents of the screen has scrolled through the boundary of themunicipality. Further, when the route to the destination is set, thescreen display apparatus may apply the reaction force to an input of theoperation information that scrolls the route out of the screen. In thismanner, the user is guided by the reaction force of the joystick 20,thereby being enabled to perform the scroll of the screen along theroute toward the destination. Furthermore, when the route to thedestination has not been set, the screen display apparatus may apply thereaction force to the operation information that scrolls the screentoward the sea. This is based on the assumption that the navigationsystem is not usually scrolled toward the sea. That is, when the userscrolls the screen toward the sea, the user is assumed to be performinga wrong operation. Therefore, by applying the reaction force to thejoystick 20, the user is notified that he/she is performing the wrongoperation.

Though the scroll with zooming is described as the scroll of the screenaccording to the operation of the input device in the above embodiments,the scroll with zooming may be applied for, for example, displaying thesearched map around the destination. That is, when the destination issearched by name, by telephone number or the like, the map may bescrolled to the searched destination with the zooming operation combinedtherewith instead of switching the current position of the map to thedestination. In this case, the route from the current position to thedestination may be guided by the scroll with zooming along the searchedroute. In this manner, the user can have an overview of the route.

The present invention is described as the screen display apparatus andits operation in the above embodiments. However, a program forcontrolling a computer to perform the process by the above-describedscreen display apparatus is within the scope of the present disclosure.

According to the present disclosure, the screen display apparatusprovides excellent advantages such as an easy zoom rate change operationto a certain zoom rate as well as the scroll of the screen with aconstant zoom rate at the time of stopping the zoom process. Inaddition, the present disclosure is applicable to various apparatusessuch as a navigation apparatus, a portable terminal, a personalcomputer, an amusement game machine, a medical image viewing apparatus,and household appliances including a video recorder, a television andthe like.

Such changes and modifications are to be understood as being within thescope of the present invention as defined by the appended claims.

What is claimed is:
 1. A screen display apparatus comprising: anoperation information reception unit that receives from an input deviceoperation information regarding an inclination direction and aninclination angle of the input device; and a screen controller thatscrolls a screen content in the inclination direction of the inputdevice based on the operation information received by the operationinformation reception unit, wherein the screen controller performs azoom-out process for zooming out by changing a zoom rate while scrollingthe screen content when the inclination angle of the input device isgreater than a first threshold, and the screen controller stops thechanging of the zoom rate and scrolls the screen content at a stoppedzoom rate when the inclination angle of the input device is detected tobe smaller than the first threshold and greater than a second threshold.2. The screen display apparatus of claim 1, wherein when the screencontent is scrolled at the stopped zoom rate, the screen controllerperforms a zoom-in process while scrolling the screen content upondetecting that the inclination angle of the input device is smaller thanthe second threshold.
 3. A method of displaying a screen comprising:receiving operation information regarding an inclination direction andan inclination angle of an input device from the input device; andscrolling a screen content in the inclination direction of the inputdevice based on the received operation information, performing azoom-out process for zooming out by changing a zoom rate while scrollingthe screen content when the inclination angle of the input device isgreater than a first threshold, and stopping the changing of the zoomrate and scrolling the screen content at a stopped zoom rate when theinclination angle of the input device is detected to be smaller than thefirst threshold and greater than a second threshold.
 4. The method ofdisplaying a screen as in claim 3, wherein when the screen content isscrolled at the stopped zoom rate, performing a zoom-in process whilescrolling the screen content upon detecting that the inclination angleof the input device is smaller than the second threshold.
 5. A screendisplay apparatus comprising: an operation information reception unitthat receives from an input device operation information regarding aninclination direction and an inclination angle of the input device; anda screen controller that scrolls a screen content in the inclinationdirection of the input device based on the operation informationreceived by the operation information reception unit, wherein the screencontroller performs a zoom-out process for zooming out by changing azoom rate while scrolling the screen content when the inclination angleof the input device is greater than a first threshold, the screencontroller performs a zoom-in process for zooming in by changing thezoom rate while scrolling the screen content when the inclination angleof the input device is smaller than a second threshold, and the screencontroller stops the changing of the zoom rate and scrolls the screencontent at a stopped zoom rate when the inclination angle of the inputdevice is detected to be smaller than the first threshold and greaterthan the second threshold.
 6. A method of displaying a screencomprising: receiving operation information regarding an inclinationdirection and an inclination angle of an input device from the inputdevice; and scrolling a screen content in the inclination direction ofthe input device based on the received operation information, performinga zoom-out process for zooming out by changing a zoom rate whilescrolling the screen content when the inclination angle of the inputdevice is greater than a first threshold, zooming in by changing thezoom rate while scrolling the screen content when the inclination angleof the input device is smaller than a second threshold, and stopping thechanging of the zoom rate and scrolling the screen content at a stoppedzoom rate when the inclination angle of the input device is detected tobe smaller than the first threshold and greater than the secondthreshold.